Various annular in cross section hollow cylindrical collector electrodes for electrostatic precipitators have been produced and operated with the well known wet wall principle wherein water flows downward on the surface of such electrodes and thereby serves as the electrostatic collector for foreign matter carried in air or gas streams passing in substantially laminar flow relationship to the surfaces of such electrodes. In some instances, each of such electrodes comprises inner and outer concentric annular walls between which water is conducted upwardly to spill over the upper edge thereof and to flow downward on inner and outer sides thereof. Such structures have been proved to be expensive to produce and maintain and have, therefore, caused considerable financial and functional problems relative to the prior art wet wall electrostatic precipitators.
Additionally, the structural support of such collector electrodes in combination with the means by which water conduits deliver water to the walls thereof have heretofore been complicated in terms of structural arrangement as well as maintenance and have, therefore, been quite costly overall. Those prior art structures having water conduits extending upwardly therethrough or those which have water channels therein tend to cause arcing through the side walls of the electrodes and into the most conductive areas. In this manner some of the prior art collector electrodes deteriorated such as to cause very difficult maintenance problems. Additionally, some of the collector electrodes having water conduits extending upward therethrough were such that the structural integrity of the electrode was compromised to the extent that accurate spacing thereof could not be maintained to a desirable degree and, in many instances, those collector electrodes which had water conductors therein experienced or developed leaks which could not be fixed without disassembling a substantial percentage of the entire precipitator structure.